new Promise((resolve, reject) => { 
  resolve("fulfilled")
  // hd = 1
  // reject("sss")
  // throw new Error("haihaihai") // 同步代码可以使用(主线程中吧大概)
}).then(
  value => new Promise((resolve, reject) => { 
  throw new Error("hahaha")
  }),
  reason => console.log(reason.message)
).then(
  value => '',
  reason => console.log(reason.message)
).catch(reason => { 
  if (typeof reason == 'bigint') { }
  if (typeof reason == 'object') { }
  if (typeof reason == 'undefined') { }
})
